The testing of new chemicals against tumors in rodents as a test system to discover new antitumor drugs has been facilitated by the development of the ability to transplant animal tumors, including human tumors, in such rodents. Such test systems form the backbone of cancer drug development programs today. (See DeVita, V. T., V. T. Oliverio, F. M. Muggia, P. W. Wiernik, J. Zeigler, A. Goldin, D. Rubin, J. Henney, and S. Schepartz, "The Drug Development and Chemical Trials Programs of the Division of Cancer Treatment, National Cancer Institute", Cancer Clin. Trials, Vol. 2 (1979), pp. 195-216; and Goldin, A., and J. M. Vendetti, "The New NCI Screen and Its Implication for Clinical Evaluation", Recent Results in Cancer Research, Vol. 70 (1980), S. K. Carter and Y. Sakurai (ed.), Springer-Verlag, Berlin, Germany.
Compound (I) and a method of synthesizing it are disclosed in the following reference: Snyder, H. R., Jr., and F. F. Ebetino, "A New Synthesis of Furo[2,3-b]pyridine Derivatives (1)", The Journal of Heterocyclic Chemistry, Vol. 3 (1966), pp. 202-205, the contents of which is hereby incorporated by reference. Compound (I) is identified as compound XVIII in this reference.